DISSERTATION RESEACH: Does phenotypic evidence support ecological speciation in western long-eared Myotis bats?

Ohio State University, The, Columbus OH

Investigators

Abstract

How species are formed is a central question in evolutionary biology. One process involved in species formation is known as ecological speciation, which occurs when different environments promote genetic diversification in a geographically widespread species. It is particularly useful to investigate and model this process in organisms that naturally disperse widely, such as bats. This project will explore differences within and among closely related species of the western long-eared Myotis bats. A novel aspect of this work will be the development of an analytical framework that tests for correlations between phenotypes and genotypes while controlling for environmental variation. This analytical pipeline will be made publicly available, and may be used to test the predictions of ecological speciation in a variety of different organisms. Results from this work will also have important practical implications to bat conservation efforts. To communicate findings from this research to a broader audience, an online interactive museum focused on the tempo and mode of speciation of Myotis bats will be developed. This research will identify phenotypic evidence of ecological speciation in western long-eared Myotis bats of North America by co-analyzing genomic, morphological, and environmental data. Previous findings demonstrate that these species follow a pattern of speciation-with-gene-flow that might have been promoted by environmental changes. Therefore the hypothesis that morphological differentiation among these bat species is associated with both divergence-with-gene-flow patterns and environmental variation will be tested. Specifically, craniodental shape and size variation among these species across different environments will be examined, using geometric morphometric approaches. A novel approach that accounts for both genetic and environmental covariation on morphometric differences within and among species will be developed. This framework will use geometric morphometrics coupled with environmental niche and genomic scan analyses to identify outlier loci that may have evolved under divergent selection. Finally, this new framework will be applied to predict morphometric variation among the western long-eared bats and differentiate between phenotypic convergence and gene flow among species. This integrative approach will allow us to understand the tempo and mode of speciation of Myotis bats from a phenotypic, genetic and environmental perspective.